title: Quality control of photosystem II: impact of light and heat stresses.
abstract: Photosystem II is vulnerable to various abiotic stresses such as strong visible light and heat. Under both stresses, the damage seems to be triggered by reactive oxygen species, and the most critical damage occurs in the reaction center-binding D1 protein. Recent progress has been made in identifying the protease involved in the degradation of the photo- or heat-damaged D1 protein, the ATP-dependent metalloprotease FtsH. Another important result has been the discovery that the damaged D1 protein aggregates with nearby polypeptides such as the D2 protein and the antenna chlorophyll-binding protein CP43. The degradation and aggregation of the D1 protein occur simultaneously, but the relationship between the two is not known. We suggest that phosphorylation and dephosphorylation of the D1 protein, as well as the binding of the extrinsic PsbO protein to Photosystem II, play regulatory roles in directing the damaged D1 protein to the two alternative pathways.
authors.affiliation: Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan. yasusiya@cc.okayama-u.ac.jp
authors.forename: Yasusi
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Ryota
authors.initials: R
authors.lastname: Aminaka
authors.forename: Miho
authors.initials: M
authors.lastname: Yoshioka
authors.forename: Mahbuba
authors.initials: M
authors.lastname: Khatoon
authors.forename: Keisuke
authors.initials: K
authors.lastname: Komayama
authors.forename: Daichi
authors.initials: D
authors.lastname: Takenaka
authors.forename: Amu
authors.initials: A
authors.lastname: Yamashita
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Nijo
authors.forename: Kayo
authors.initials: K
authors.lastname: Inagawa
authors.forename: Noriko
authors.initials: N
authors.lastname: Morita
authors.forename: Takayuki
authors.initials: T
authors.lastname: Sasaki
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yamamoto
mesh_terms: D000222:Adaptation, Physiological; D006358:Hot Temperature; D008027:Light; D010447:Peptide Hydrolases / Q000378:metabolism; D010766:Phosphorylation; D045332:Photosystem II Protein Complex / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013312:Stress, Physiological; D020524:Thylakoids / Q000648:ultrastructure
chemical_list: D045332:Photosystem II Protein Complex; D017382:Reactive Oxygen Species; D010447:Peptide Hydrolases